1. Field of the Invention
The present invention relates to an apparatus for penetrating and for observing penetration of body tissue. More particularly, the present invention relates to a trocar assembly having an endoscope or laparoscope inserted therethrough to provide visual observation during penetration of the peritoneum or other body tissue.
2. Description of the Related Art
Endoscopic surgical procedures, that is, surgical procedures performed through tubular sleeves or cannulas, have been utilized for many years. Initially, endoscopic surgical procedures were primarily diagnostic in nature. More recently as endoscopic technology has advanced, surgeons are performing increasingly complex and innovative endoscopic surgical procedures. In endoscopic procedures, surgery is performed in any hollow viscus of the body through a small incision or through narrow endoscopic tubes (cannulas) inserted through small entrance wounds in the skin. In laparoscopic procedures surgery is performed in the interior of the abdomen.
Laparoscopic procedures generally utilize instrumentation that is internally sealed to inhibit gases from entering or exiting the body through the laparoscopic or endoscopic incision. This is particularly true in surgical procedures in which the surgical region is insufflated. Moreover, laparoscopic and endoscopic procedures often require the surgeon to act on organs, tissues and vessels far removed from the incision, thereby requiring that any instruments to be used in such procedures be of sufficient size and length to permit remote operation. Typically, after the surgical region is insufflated, trocars are used to puncture the body cavity and include a cannula which remains in place for use during endoscopic procedures. Generally, trocars used during such procedures include a stylet having a sharp tip for penetrating the body cavity positioned coaxially within protective tubes to protect a patient or surgeon from inadvertent contact with the tip. An example of a known trocar is described in commonly assigned, U.S. Pat. No. 4,601,710 to Moll. Most currently used trocars rely on protective tubes or relative retraction of the tip to prevent inadvertent contact with tissue.
The present invention provides a trocar assembly for observing the penetration of the peritoneum or other body portions. The trocar assembly of the present invention provides an improved window structure for passing optical images to an imaging system inserted into or formed within the trocar assembly, which provides a clear and bright image of the body tissue being penetrated. The assembly also includes a light pipe for passing illumination light to body tissue. In addition, the present invention provides an improved cutting tip for penetration of body tissue.